Answer:Valves stop blood flowing backwards
Explanation: Valve are flags of tissue that control the direction of the blood in our heart.,it prevent the backwards flow of blood. valves regulate blood from flowing back into the atria.The right and left atrio-ventricular valves prevent blood from flowing backwards into atria. When the ventricle is full,the valve prevent backwards flow of blood.
Answer:
The moon moves through space in two ways: It revolves around Earth and also rotates on its own axis. The moon rotates once on its axis in the same time that it takes to revolve once around Earth. The changing relative positions of the moon, Earth, and sun cause the phases of the moon.
Explanation:
B.
Answer:
The positive charge of the histone proteins get reduced due to the process of histone acetylation, thus making the wrapping of DNA around the histones less tightened. The loose connected DNA afterward associates with the transcription factors for the articulation of the genes situated in that area.
Generally, when there is no requirement of gene anymore, the acetyl groups from the histones get withdrawn by the activity of histone deacetylase enzyme (HDAC9) that makes the DNA tightly wrapped and inaccessible again. In case, when less expression of histone deacetylase enzyme occurs, the process of deacetylation fails to take place. This indicates that within an immune cell, at the time of infection, the inflammatory gene, which was made available does not get re-wrapped firmly around the histones.
Answer:
D
Explanation:
The intake of someone of the that weight should be 73 ounces you haven't given me any form of formula so I went with the highest.